LNF Facilities on the collider DAΦNE


Electron Positron Collider DAFNE
It consists of a double ring collider for electrons and positrons with 510 MeV energy per beam. More in detail, a high current linac produces up to 500 mA electron and 100 mA positron beams, feeding them to a ring where they are stacked and damped; from the damping ring they are injected into two identical but separate storage rings. The two rings cross at two interactions points where the experiments are installed. DAFNE is a multi-bunch accelerator, with 120 bunches/beam, where has been achieved a luminosity of 1.6×10^32 cm­² s­¹. In 2006 DAFNE completed the first KLOE run integrating 2 fb­¹.


Particle and Nuclear physics facilities

The particle and nuclear physics research is carried out at the electron-positron collider DAΦNE. The collisions of the 510 MeV electron and positrons beams produce abundantly φ-mesons, which in turn promptly decay into kaon pairs. Taking advantage of the high luminosity, several high-precision experiments are being carried out with three detectors: the K-Long Experiment (KLOE) for the study of the CP symmetry violation and for precision particle physics measurements; a high resolution nuclear physics detector (FINUDA) mainly devoted to hypernuclear spectroscopy; a detector for precision measurements in the field of exotic atoms (SIDDHARTA), thanks to a good energy resolution, very high stability and unprecedented background rejection capability of its triggerable X-ray detector.

  • FINUDA apparatus is a multilayered magnetic spectrometer based on a superconducting solenoid of length 240 cm and radius 122 cm, able to operate with magnetic field as high as 1.0 Tesla. It has been designed to explore the reaction channels deriving from the interactions of slow charged kaons on nuclei. In particular FINUDA is able to study, simultaneously, hypernuclear spectroscopy and hypernuclear decay modes, with a momentum resolution of up to 0.33% (corresponding to about 800 keV on hypernuclear levels). Charged particles emitted following charged kaon interactions in the target nuclei (up to 8 different targets can be simultaneously explored) are detected by several detectors, each optimized to a specific task: Si bi-dimensional microstrips to detect the interaction vertex; drift chambers and straw tubes to reconstruct charged particles trajectories; plastic scintillators for signal triggering, time-of-flight measurement and neutron detection.

  • KLOE experiment has been designed for the study of CP, CPT violation in the neutral kaon system. Its unique feature consists in producing kaon pairs, KS KL and K+ K­ , in a pure quantum state from the two body Φ-decay, thus allowing to get intense, pure, monochromatic and tagged kaon beams. It is composed of two main detectors: a fine sampling lead scintillating fiber calorimeter, EMC, for the energy and time measurement and neutral vertex reconstruction, and a light material cylindrical drift chamber, DC, for high precision and efficient tracking of charged particles. The detector is immersed in a 0.52 T magnetic field provided by a large superconductive coil. The detector is read-out by a very high bandwidth data acquisition system. A powerful computing farm, with a large and robotized storage system, is then used for online monitoring, offline data reconstruction, simulation and user analysis.

  • SIDDHARTA facility optimally combines the unique qualities source of intense, low energy, monochromatic K- beam from the decay of the φ-mesons produced at DAΦNE with the excellent precision X-ray detectors, represented by the new large area triggerable Silicon Drift Detectors (SDD), developed in the framework of the collaboration, to perform an extensive exotic atoms research programme. SIDDHARTA continues and deepen the scientific line pioneered by the DEAR experiment, which performed the most precise measurement on kaonic hydrogen, with the goal to push into the eV realm of precision the kaonic hydrogen measurement and to perform the first measurement of the elusive kaonic deuterium atom. The SIDDHARTA facility is characterized by a unique combination of the triggerable SDD X-rays detectors, highly flexible and stable precision readout electronics, extreme precision (<0.1 %) high and low voltages supplies, and high technology cryogenic and pressurized hydrogen/deuterium targets, being the first application of the SDDs as triggerable detectors for precision X-ray measurements.











Beam Test Facility

The DAΦNE Beam-Test Facility (BTF), operating at the Frascati National Laboratory of INFN (LNF), provides electron or positron beams with tuneable energy from 50 MeV to 750 MeV, while the intensity can be varied from1010/pulse, down to a single particle per pulse. The pulse width is of 1 or 10 ns, with a maximum repetition rate of 50 Hz. Since the end of 2005 a photon tagging system has been designed, built and tested. During 2006 a pulsed dipole magnet has been inserted at the end of the LINAC, allowing to continuously delivering beam in the BTF experimental area also during DAFNE main ring injection.





















DAΦNE-Light Laboratory

Is the Synchrotron Radiation Facility at the Laboratori Nazionali di Frascati (LNF). Actually three beamlines are operational using, in parasitic and dedicated mode, the intense photon emission of DAFNE, a 0.51 GeV storage ring with a routinely circulating electron current higher than 1 Ampere.

Two of these beamlines, the soft X-ray and the UV one, have as synchrotron radiation source one of the DAFNE wiggler magnets, while the third beamline, SINBAD-IR, collects the radiation from a bending magnet.

The soft X-ray beamline is equipped with a Toyama double-crystal monochromator based on the 'boomerang' mechanism that ensures a fixed-exit beam, while scanning the whole energy range that goes from 900 eV to about 3100 eV.

The wiggler mirror deflected UV beamline is equipped with a Jobin-Yvon monochromator where a holographic diffraction grating blazed at 250 nm allows to select photons in the range 200÷600 nm within a 0.1÷0.3% spectral band. The Synchrotron Infrared Beamline At DAFNE (SINBAD) covers the whole infrared domain from 10 to 10000 cm-¹ and is equipped with two end stations. The first one is a Bruker Equinox 55 interferometer. One of its exit ports hosts the microscope Hyperion 3000, working both in transmission and reflection mode and operating in the near- mid- and far-IR range down to about 200 cm-¹. The second end station is another Equinox 55 actually working with conventional sources.





















Facilities contact persons

Facility Contact Person
Electron-Positron Collider DAFNE G. Mazzitelli
Particle and Nuclear Physics F. Bossi (Kloe), C. Curceanu (Siddharta),
V. Lucherini (Finuda)
Beam Test Facility G. Mazzitelli
Dafne-Light Laboratory A. Balerna (XR) M. Cestelli (IR)


TARI FP6 staff: C. Guaraldo (Manager), G.Basso, C. Conti, D. Ferrucci - email: tari2@lnf.infn.it

Giuliano Basso - Last updating on 19 November, 2007